The ultimate objectives are to fully describe and quantify the extent of chemosensory dysfunction in the elderly, to understand its etiology, to identify in the chemical senses any mechanisms which may be common to aging of other sensory systems, and to elucidate the relationship between chemosensory function and nutritional status in the elderly. The specific aims of this application are to investigate the processes of adaptation to and recovery from chemosensory stimulation in the elderly, to determine the contributions of changes in nasal airway resistance and nasal disease to chemosensory dysfunction in the elderly, and to examine the relationship of nutritional status to chemosensory changes in the elderly. Subjects in these studies will be ambulatory, non-institutionalized adults with no hospitalizations in the year preceding testing. They will be drawn from four age groups: young, middle-aged, elderly, and the oldest-old. Both classical and modern psychophysical techniques will be used to assess chemosensory function: two-alternative, forced-choice, detection threshold and preference threshold methods; magnitude estimation and magnitude matching of intensity; and line-scaling of preference. Nasal airway resistance will be measured by anterior rhinomanometry. Nasal disease will be assessed by ear, nose and throat examinations, including endoscopy and nasal cytology. Nutritional status will be assessed using both biochemical indices and three-day dietary records. A more complete understanding of chemosensory function in the elderly may suggest methods for improving taste and smell perception, food palatability and hence, dietary intake and nutritional status in the geriatric population.